If anyone has some cool snippets to share please feel free to leave them in a comment below.
*last updated: 23 December 2016
user knob value in an expression / particle expression
[value yourUserKnob] |
random particle colour with particle expression node
*** a blendMat node must be applied before the emitter:
operation: plus surface blend: modulate |
the “color” parameter of a particleExpression node can be set using a 3dVector:
v( r, g, b )and each channel can be referenced like this:
the red value for example :
x(color)give the colour parameter a random value – (needs to be a 3dVector)
v(random*2, random, random/1.4 )
iterate over the animation curve of a Transform node copying the value of the Y position to a parameter of another Transform node.
dest = nuke.nodes.Transform() destTransform = dest["translate"] destTransform.setAnimated() destAnim = dest["translate"].animation(1) a = nuke.selectedNode()["translate"] ypos = a.animation(1) keys = ypos.keys() for a in range(0,42): dest["translate"].animation(1).setKey(a, ypos.evaluate(a)) |
display the current duration since the first frame (useful when sequence doesn’t start at zero/one)
put this in a text node or in a node’s “label” tab
[python {int( nuke.frame() - nuke.root()['first_frame'].value() ) }] |
take a RotoPaint and change each layer’s RGBA to a grey level based on it’s “depth” – useful for prep’ing for a stereo conversion i’d imagine
import random a = nuke.selectedNode() if a.Class() == "RotoPaint": knob = a['curves'] i = 0.0 for c in knob.rootLayer: pos = float ((len(knob.rootLayer) - i) / len(knob.rootLayer)) i = i+1 attrs = c.getAttributes() attrs.set(1, attrs.kRedOverlayAttribute, pos) attrs.set(1, attrs.kRedAttribute, pos) attrs.set(1, attrs.kGreenOverlayAttribute, pos) attrs.set(1, attrs.kGreenAttribute, pos) attrs.set(1, attrs.kBlueOverlayAttribute, pos) attrs.set(1, attrs.kBlueAttribute, pos) attrs.set(1, attrs.kAlphaOverlayAttribute, pos) attrs.set(1, attrs.kAlphaAttribute, pos) |
for all selected Tracker nodes multiply their track values by a factor of 4
for a in nuke.selectedNodes(): if a.Class()=="Tracker3": def scaleMe(track): if track.isAnimated(): for j in range (0,2): anim = track.animation(j) keys = anim.keys() scaleFactor = 4 while keys: keys.pop().y *= scaleFactor #i am sure there is a much nicer way of iterating over all the knobs but this worked for what i quickly needed t1 = a['track1'] t2 = a['track2'] t3 = a['track3'] t4 = a['track4'] scaleMe(t1) scaleMe(t2) scaleMe(t3) scaleMe(t4) |
set bbox to “B” for nodes inside all Group nodes
import nuke def bboxGroup(): for b in nuke.allNodes(): if b.Class() == "Group": for a in nuke.toNode(b.name()).nodes(): classTypes = ['Merge' , 'Keymix', 'Copy', ] print a.name() for n in classTypes: if n in a.Class(): try: for p in a['bbox'].values(): if 'B' in p: a['bbox'].setValue(a['bbox'].values().index(p)) except: pass |
“Autowrite” node
Copy the following line into the python “beforeRender” field in a write node.
The write node’s “file” field will be filled based on the script’s name/path.
Obviously this all depends on your pipeline etc.
For my current situation each vfx shot has it’s own directory, which is then populated with “renders” & “scripts” subdirectories.
So for me I can do this:
nuke.thisNode()["file"].setValue(nuke.root().name().replace("scripts","renders").replace(".nk",".mov")) |
delete all nodes that are not selected
s = nuke.selectedNodes() b = nuke.allNodes() for n in b: if n not in s: nuke.delete(n) |
selects all dependencies (input nodes & their parents) from a selected node
a = nuke.selectedNode() nodesToSelect = [] nodesToSelect.append(a) def climb(node): # print node.name() for n in node.dependencies(): nodesToSelect.append(a) climb(n) climb(a) for x in nodesToSelect: print x.name() # x.setSelected(1) |
set all Read nodes to cache locally
for a in nuke.allNodes(): if a.Class()=='Read': a['cached'].setValue(1) a['cacheLocal'].setValue(0) |
print last frame of script
print nuke.root()['last_frame'].value() |
create a backdrop based on selected Nodes
margin = 100 xpMax = nuke.selectedNode().xpos() xpMin = nuke.selectedNode().xpos() ypMax = nuke.selectedNode().ypos() ypMin = nuke.selectedNode().ypos() for a in nuke.selectedNodes(): if a.xpos() > xpMax: xpMax = a.xpos() if a.xpos() < xpMin: xpMin = a.xpos() if a.ypos() > ypMax: ypMax = a.ypos() if a.ypos() < ypMin: ypMin = a.ypos() bd = nuke.nodes.BackdropNode(bdwidth=(xpMax-xpMin)+margin, bdheight=(ypMax-ypMin)+margin) bd.setXpos(xpMin-margin/2) bd.setYpos(ypMin-margin/2) |
disable “postage stamps” on only “Read” nodes
for a in nuke.allNodes(): if a.Class()=='Read': a['postage_stamp'].setValue(0) |
disable “postage stamps” on all nodes
for a in nuke.allNodes(): try: a['postage_stamp'].setValue(0) except: pass |
“unhide” all nodes’ inputs – useful when receiving a sneaky comp/lighting script
for a in nuke.allNodes(): try: a['hide_input'].setValue(0) except: pass |
change the “first” frame of all selected nodes that are “Read” nodes:
(example changes the first frame to 1018)
for a in nuke.selectedNodes(): if a.Class() == 'Read': a['first'].setValue(1018) |
print a selected nodes’ methods
import struct node = nuke.selectedNode() for a in node['lookup'].animations(): print dir(a) |
print inputs (dependencies) of a selected node:
for a in nuke.selectedNode().dependencies(): print a.name() |
print outputs (dependents) of a selected node:
for a in nuke.selectedNode().dependent(): print a.name() |
find all the TimeOffset nodes in a Group called “Group2”, and change the value of each offset based on it’s position in the array of found time offsets
tos = [] for a in nuke.toNode('Group2').nodes(): if a.Class()=='TimeOffset': tos.append(a) for b in tos: b['time_offset'].setValue(tos.index(b)) |
set the ‘bbox’ for any selected Merge, Keymix & Copy nodes to “B”
for a in nuke.selectedNodes(): classTypes = ['Merge' , 'Keymix', 'Copy', ] for n in classTypes: if n in a.Class(): for p in a['bbox'].values(): if 'B' in p: a['bbox'].setValue(a['bbox'].values().index(p)) |
remove all animation from a selected nodes
for a in nuke.selectedNode().knobs(): nuke.selectedNode()[a].clearAnimated() |
add keyframes – animate a mix
for a in nuke.selectedNodes(): a['mix'].setAnimated() a['mix'].setValueAt(1,nuke.frame()) a['mix'].setValueAt(0,(nuke.frame() - 1)) |
half the colour value of all the Constant nodes in a script
for a in nuke.allNodes(): if a.Class() == "Constant": a['color'].setValue(a['color'].value()[0] / 2 , 0) a['color'].setValue(a['color'].value()[1] / 2 , 1) a['color'].setValue(a['color'].value()[2] / 2 , 2) |
find all the transform nodes in a script, and if their input is a Crop, set the ‘scale’ value to be twice it’s current value (also checks if the scale is a list/array or a float)
for a in nuke.allNodes(): if a.Class() == "Transform": if a.input(0).Class() == "Crop": x = a['scale'].value() if type(x).__name__ == 'list': a['scale'].setValue(x[0] * 2 , 0) a['scale'].setValue(x[1] * 2 , 1) if type(x).__name__ == 'float': a['scale'].setValue(x*2) |
set all the gain values of all ColorCorrect nodes to be twice their current value
for a in nuke.allNodes(): if a.Class() == "ColorCorrect": a['gain'].setValue(a['gain'].value() * 2) |
print files with ‘mov’ in filename
for a in nuke.allNodes(): if 'Read' in a['name'].value(): if 'mov' in a['file'].value(): print a['file'].value() |
change font size of all “write” nodes in script
for a in nuke.selectedNodes(): if "Write" in a['name'].value(): a['note_font_size'].setValue(60) |
create 20 constants with incrementing colour values
def makeConstants(amount): for i in range(amount): a= nuke.nodes.Constant() color= float( float(i) / float(amount) ) a['color'].setValue(color) makeConstants(20) |
change the name of all Text nodes to contents the text “message”
for a in nuke.allNodes(): if a.Class()=='Text': a.setName(a['message'].value()) |
##Expressions
(in an expression node) – alpha channel – if the y value of the pixel is even, make it 0, else make it 1 (for viewing fields?)
y%2==1?0:1